A book that celebrates Germany’s timesaving contribution to global cuisine is among the contenders for the 2018 Diagram prize for the oddest title of the year. The Joy of Waterboiling may sound like the latest trend in mindfulness, but it is in fact a guide to cooking in a kettle.

Run by trade magazine the Bookseller, over the past 40 years the literary world’s strangest prize has celebrated odd, peculiar and head-scratching titles regardless of the merit of what lies between the covers.

Written in German, The Joy of Waterboiling is the first foreign language book in contention for the Diagram. A spokesman for the Bookseller said: “I admit there was some robust discussion – by that I mean a punch-up between judges – whether it should be allowed in, but a check of the rules revealed that only the title need be in English.”

Managing editor and judge Tom Tivnan added that opening up the prize to European entrants was an appropriate response to Brexit: “Publishing should cross borders and this is the first pro-European Diagram prize.”

As usual the sextet of titles shortlisted is dominated by academic texts. Citing Hoe-Chi Angel Au’s contribution to queer studies, Are Gay Men More Accurate in Detecting Deceits?, Tivnan said: “It follows a long Diagram line of books from university eggheads tone-deaf to how their titles might scan to the general public.”

Animal husbandry continues to provide a rich seam of inspiration for the judges. Cornelia Klarholz and Andrea Schachinger will this year be hoping their title about acupuncture for horses, Equine Dry Needling, will follow in the footsteps of 2017’s winner, The Commuter Pig Keeper.

Bringing up the rear of the 2018 shortlist are two titles from horticulture and business. Any topiarists who has wondered “what would Jesus do?” while cutting the privet will find answers in Methodist minister David Muskett’s Jesus on Gardening.

The final title on the shortlist is entrepreneur Paul Oberschneider’s Why Sell Tacos in Africa?, chosen by the judges because of the author’s seeming ignorance of what the Mexican snack contains. The businessman claims the book will show there are “no magic beans” for success, but, the judges pointed out, “beans are often in tacos, so go figure”.

A “passable bottle of claret” will be awarded to the author of the winning title and to a voter for the winning entry chosen at random. The public vote closes on 16 November and the winner will be announced on 23 November.